1. Field of the invention
The present invention relates to an apparatus for elevating a spindle assembly of a disc player. More particularly, the present invention relates to an apparatus for elevating a spindle assembly of a disc player which can play selectively a compact disc and a minidisc by using a single pickup device and a single spindle assembly of which the height can be automatically adjusted in accordance with kinds of discs.
2. Description of the Prior Arts
Nowadays, each of minidisc player and compact disc player is used for reproduction of only the respective type of the disc. Thus, when a user wants to obtain information from different types of discs, he should separately buy a new player applicable thereto.
In general, the disc which is at a naked state or at an encased state in a cartridge is mounted on the tray to be loaded on the player. These disc loading methods depend on the disc player's structure, so that the user can not load the disc by his own selection in view of the disc player's structure. Also, in fields of a common disc player used for reproducing discs of different sizes, although products which can reproduce the discs of different sizes such as a laser disc (LD), a compact disc (CD), etc. are being manufactured, those can be applicable only to the discs of different sizes which are at the naked state.
Further, Katsuichi Sakurai et al. proposed a disc player capable of reproducing both a naked disc and a cartridge-encased disc in E.P. Publication 525201 A2 (corres. U.S.Pat. No. 5,299,185).
Also, Hideo Kawachi et al. proposed the disc player capable of reproducing both a naked disc and a cartridge-encased disc in E.P. Publication 518259 A3 (corres. U.S. Pat. No. 5,301,176). However, the above disc player can reproduce the disc having the same size (or diameter).
Recently, an MD/CD disc player which can selectively reproduce a CD and an MD by using a single optical pickup device and a single spindle assembly having a turntable, a spindle motor and a spindle shaft has been developed in order to solve problems of the prior art minidisc player and compact disc player.
In the MD/CD disc player provided with the single spindle assembly and the single pickup device, in order that the MD or the CD can be selectively mounted on the turntable constituting the spindle assembly, a double structure wherein there is a predetermined height difference between a compact disc tray and a minidisc tray is necessary in the disc player. Also, the MD is mounted on an upper portion of the turntable constituting the spindle assembly and the CD is mounted on a lower portion of the turntable constituting the spindle assembly. Further, in the double structure having a double tray structure and a turntable structure, since when reproducing the disc, a predetermined distance between the discs which are mounted on the respective trays and the pickup device should be always maintained, the height of the spindle assembly should be adjusted in accordance with the tray on which the desired disc is mounted.
In the above Hideo Kawachi et al. patent, there is also disclosed an apparatus for elevating the spindle assembly wherein one side of a chassis supporting the spindle assembly is fixed to a main chassis of the disc player and the spindle assembly can be moved up and down in a radial direction centering around the fixing point. However, the apparatus for elevating the spindle assembly can be applicable to the naked and cartridge-encased discs of only the same size, so that the disc player should be changed in its structure in order to drive the MD and CD having different sizes. In addition, since only one end of spindle assembly elevating apparatus is moved reciprocatingly while the other end is fixed, it is difficult to precisely adjust a position of the spindle assembly.